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GSM 4-Way Extension Lead – Voice Monitoring & Call-Back Function
  • GSM 4-Way Extension Lead – Voice Monitoring & Call-Back Function
GSM 4-Way Extension Lead – Voice Monitoring & Call-Back Function

GSM 4-Way Extension Lead – Voice Monitoring & Call-Back Function

£90.00

Voice-Activated GSM Extension Lead – 4-Way Mains Adapter with Call-Back

Powerful. Covert. Always connected. The Voice-Activated GSM Extension Lead is a discreet surveillance device built inside a fully functional 4-way mains power adapter. Designed and assembled in the UK, it combines everyday utility with advanced GSM audio monitoring technology, letting you listen in real-time from anywhere in the world.

With dual built-in microphones and voice-triggered call-back mode, this intelligent listening device automatically dials your number when it detects sound in the room. Simply insert a compatible SIM card, plug it into a wall socket, and call the number to hear clear, live audio — all without lights, beeps, or visible indicators. The mains-powered design means continuous operation for long-term monitoring at home, work, or in storage spaces.

  • Hidden in a Working 4-Way Mains Adapter – Powers appliances while monitoring discreetly
  • Voice-Activated Call-Back Function – Automatically calls you when sound or conversation is detected
  • Real-Time Audio Monitoring – Dial the SIM number to listen instantly, anywhere in the world
  • Unlimited Range – GSM connectivity ensures clear reception with no distance limits
  • Continuous Power Supply – Mains-powered for 24/7 operation, no recharging required
  • Dual Microphones – Captures sound accurately from up to 10 metres away
  • SMS-Controlled Settings – Activate or disable call-back mode remotely via text message
  • UK Manufactured by Empe Trading – Professionally assembled and tested for reliability
  • Network Compatibility – Best with EE or Lebara SIMs (not compatible with O2 or Three)

What’s Included

  • GSM 4-Way Extension Lead Listening Device
  • User Manual

  Dimensions (LxWxD)

  • 250 × 50 × 20 mm
  • 450 g
Shipping & Returns

All orders are shipped fully tracked.

Please see our Shipping & Returns Policy for more information on delivery.
Usage Disclaimer

This product must not be used for any unlawful purposes. Unauthorized audio or video recording of individuals without their knowledge and/or consent may be a criminal offense under applicable laws. Users are solely responsible for ensuring compliance with all relevant regulations.
Our Story

We launched in the UK with a single aim: deliver dependable, discreet surveillance gear, without the hype. Fed up with flimsy “spy toys”, we source pro-grade tools that are tested in the field, easy to use, and made to endure. We equip investigators, small firms, and everyday people to protect what matter, always lawfully and responsibly. Orders ship fast and in plain packaging, with clear guides and friendly support from folks who actually rely on this kit.
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Frequently asked questions
Q: How does the GSM Extension Lead work?

The GSM Extension Lead operates using a SIM card and GSM network connection, allowing you to listen to the surrounding environment remotely. Once a SIM is inserted, simply call the device’s number to hear real-time audio. You can also enable voice-activated call-back mode so the unit automatically calls you when it detects sound.
Q: Does the device require Wi-Fi or internet to function?

No, this device works exclusively through the GSM mobile network, not Wi-Fi. It functions like a miniature mobile phone, so you can listen live from anywhere in the world by calling the inserted SIM card directly. No apps or internet setup required.
Q: Can it operate continuously without charging?

Yes. Because it’s built into a fully functional 4-way mains power adapter, it draws constant power from the wall, allowing 24/7 continuous monitoring. It also powers connected appliances normally, making it completely discreet for long-term use.
Q: What SIM cards are compatible with the GSM Extension Lead?

For best performance, we recommend using an EE or Lebara SIM card. Each device is tested in the UK using EE’s network. The unit is not compatible with O2 or Three (3) networks due to frequency restrictions.
Q: Is it legal to use a GSM listening device in the UK?

Yes, it’s legal to own and use for personal or property protection purposes, such as monitoring your home or workspace. However, recording or monitoring private conversations without consent may breach UK privacy laws. Always ensure use complies with GDPR and UK data protection regulations.

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